I just recently learned this and thought I would pass it on.
A box scale is a scale that can be played anywhere on the neck. where you play it determines the key of the scale.
I will give the fingering since the notes are subject to location on the neck.
It is played on any 4 frets with each of your 4 fingers assigned to a fret.
Starting on the:
6th string play fingers 2 then 4
5th string fingers 1, 2, 4
4th string fingers 1,3, 4
3rd string fingers 1,3,4
2nd string fingers 2,4
first string fingers 1,2
The first note played with finger number 2 on the 6th string is the key of the scale. Example if I play the scale from the 4th fret to the 7th fret the first note played by my middle finger is on the 5th fret so the scale is in the key of A.
Hope this does someone some good.
Just a little precision: the scale you're playing is the major scale of the key of the note you start with (6th string second fret)
